Ring-like elastic belt with improved side seams

Abstract

Disclosed is a ring-like elastic belt having a longitudinal direction and a lateral direction comprising: a pair of side seams which join the lateral edges of the front belt and the back belt such that the front fold over and the back fold over cooperatively define a distal edge of the ring-like elastic belt, the side seam made by a hot air bond which at least partially melts material of the elastic laminate, the side seam having continuity of the melted material along the substantial entirety of its longitudinal dimension; wherein the side seam has a Belt Minimum Peel Strength of at least about 6N/25 mm, a Belt Maximum Peel Strength of no more than 18N/25 mm, and a Top Bottom Difference of no more than 15%, according to the measurements herein.

What is claimed is: 
     
         1 . A ring-like elastic belt having a longitudinal direction and a lateral direction comprising:
 a front belt and a back belt, each of the front belt and back belt being an elastic laminate comprising a first substrate layer, a second substrate layer, and a plurality of elastic bodies joined between the first substrate layer and the second substrate layer, each of the front belt and the back belt further comprising a fold over of at least one of the first substrate layer and the second substrate layer wherein the fold over of the front belt has a longitudinal dimension shorter than the front belt, and the fold over of the back belt has a longitudinal dimension shorter than the front belt,   a pair of side seams which join the lateral edges of the front belt and the back belt such that the front fold over and the back fold over cooperatively define a distal edge of the ring-like elastic belt, the side seam made by a hot air bond which at least partially melts material of the elastic laminate, the side seam having continuity of the melted material along the substantial entirety of its longitudinal dimension;   wherein the side seam has a Belt Minimum Peel Strength of at least about 6N/25 mm, a Belt Maximum Peel Strength of no more than 18N/25 mm, and a Top Bottom Difference of no more than 15%, according to the measurements herein.   
     
     
         2 . The belt of  claim 1 , wherein the side seam has an Average Peel Strength and the combined first and second substrate layer has a Material Breaking Point according to measurements herein, wherein the Average Peel Strength is from about 20% to about 50% of the Material Breaking Point. 
     
     
         3 . The belt of  claim 1 , wherein each of the first substrate layer and the second substrate layer has a Material Breaking Point according to the measurements herein, wherein the Material Breaking Point is less than about 8N. 
     
     
         4 . The belt of  claim 1 , wherein the elastic bodies are disposed in a manner such that at least one elastic body from the front belt and at least one elastic body from the back belt overlap with each other at the side seam. 
     
     
         5 . The belt of  claim 1 , wherein the elastic bodies are intermittently disposed in varying intervals, wherein the pattern of intervals of elastic bodies disposed on the front belt is different from the pattern of intervals of the elastic bodies disposed on the back belt. 
     
     
         6 . The belt of  claim 1 , wherein the belt has a maximum basis weight of at least about 90 gsm. 
     
     
         7 . The belt of  claim 1 , wherein the longitudinal dimension of the front belt is different from the longitudinal dimension of the back belt, wherein the distal edges of the front belt and back belt are matched with each other. 
     
     
         8 . The belt of  claim 1 , wherein the first substrate layer and the second substrate layer are nonwoven materials having difference in at least one of basis weight, stiffness, and texture. 
     
     
         9 . The belt of  claim 8 , wherein at least one of the first substrate layer and the second substrate layer has a plurality of openings or bondings. 
     
     
         10 . The belt of  claim 8 , wherein the first substrate layer is a nonwoven fabric made of air-through carded fibers. 
     
     
         11 . A wearable article comprising a center chassis and a ring-like elastic belt according to any of the preceding claims wherein the center chassis is bridged from the center of the front belt to the center of the back belt. 
     
     
         12 . A method of manufacturing a ring-like elastic belt comprising steps of:
 advancing a continuous first substrate layer in a machine direction, the continuous first substrate layer having a first surface and an opposing second surface and defining a width in a cross machine direction;   advancing a continuous second substrate layer in the machine direction, the continuous second substrate layer having a first surface and an opposing second surface and having a smaller width than the continuous first substrate layer;   advancing a plurality of elastic bodies in the machine direction in a stretched state;   joining the elastic bodies between the first surface of the continuous first substrate layer and the first surface of the continuous second substrate layer;   cutting the assembly in the machine direction where the continuous first substrate layer and continuous second substrate layer are overlayed to define a continuous front belt and a continuous back belt;   folding the continuous first substrate layer along the machine direction of at least one of the continuous front belt and the continuous back belt, the folded portion of the continuous first substrate layer defining a continuous fold over region;   overlaying the continuous front belt and the continuous back belt such that the cross machine edges of the continuous front belt and the continuous back belt are matched; and   intermittently seaming the obtained assembly by directing a jet of heated air to at least partially melt the substrates of the continuous front belt and the substrates of the continuous back belt, and compressing the melted portion between an outer circumferential surface of an anvil roll and a pressing member;   wherein the outer circumferential surface of the anvil roll comprises a grooved region having a repetition of intermittently indented surfaces alternating in the cross machine direction and a flat region devoid of the intermittent indented surfaces, wherein the continuous fold over region is configured to meet the grooved region of the anvil roll upon compression.   
     
     
         13 . The method of  claim 12 , wherein the pressing member comprises a regular surface and an indented surface, wherein the continuous fold over region is configured to meet the indented surface of the pressing member. 
     
     
         14 . A method of manufacturing a ring-like elastic belt comprising steps of:
 advancing a continuous first substrate layer in a machine direction, the continuous first substrate layer having a first surface and an opposing second surface and defining a width in a cross machine direction;   advancing a continuous second substrate layer in the machine direction, the continuous second substrate layer having a first surface and an opposing second surface and having a smaller width than the continuous first substrate layer;   advancing a plurality of elastic bodies in the machine direction in a stretched state;   joining the elastic bodies between the first surface of the continuous first substrate layer and the first surface of the continuous second substrate layer;   cutting the assembly in the machine direction where the continuous first substrate layer and continuous second substrate layer are overlayed to define a continuous front belt and a continuous back belt;   folding the continuous first substrate layer along the machine direction of at least one of the continuous front belt and the continuous back belt, the folded portion of the continuous first substrate layer defining a continuous fold over region;   overlaying the continuous front belt and the continuous back belt such that the cross machine edges of the continuous front belt and the continuous back belt are matched; and   intermittently seaming the obtained assembly by directing a jet of heated air to at least partially melt the substrates of the continuous front belt and the substrates of the continuous back belt, and compressing the melted portion between an outer circumferential surface of an anvil roll and a pressing member;   wherein the pressing member comprises a regular surface and an indented surface, wherein the continuous fold over region is configured to meet the indented surface of the pressing member.   
     
     
         15 . A method of manufacturing a ring-like elastic belt comprising steps of:
 advancing a continuous first substrate layer in a machine direction, the continuous first substrate layer having a first surface and an opposing second surface and defining a width in a cross machine direction;   advancing a continuous second substrate layer in the machine direction, the continuous second substrate layer having a first surface and an opposing second surface and having a smaller width than the continuous first substrate layer;   advancing a plurality of elastic bodies in the machine direction in a stretched state;   joining the elastic bodies between the first surface of the continuous first substrate layer and the first surface of the continuous second substrate layer;   cutting the assembly in the machine direction where the continuous first substrate layer and continuous second substrate layer are overlayed to define a continuous front belt and a continuous back belt;   folding the continuous first substrate layer along the machine direction of at least one of the continuous front belt and the continuous back belt, the folded portion of the continuous first substrate layer defining a continuous fold over region;   overlaying the continuous front belt and the continuous back belt such that the cross machine edges of the continuous front belt and the continuous back belt are matched; and   intermittently seaming the obtained assembly by directing a jet of heated air to at least partially melt the substrates of the continuous front belt and the substrates of the continuous back belt, and compressing the melted portion between an outer circumferential surface of an anvil roll and a pressing member;   wherein the compression is conducted for at least 2 times.   
     
     
         16 . The method of  claim 15 , wherein the compression comprises a first compression and a second compression, wherein the region of compressing of the first compression and second compression vary over the longitudinal dimension of the side seam.